How much energy was produced in this reaction? The speed of light 3*10 to the 8th power m\s?

Question

Two isotopes of hydrogen fuse to form helium. The mass of the helium is 3.12*10 negative10th power kg
less than the combined mass of the two hydrogen atoms.

Answer 1

28.08 x 10^-4 J

Answer 2

U can simply use simple algebraic addition and subtraction to get the difference in mass on both the sides of the reaction and use Einsteins most famous formula,

E = mc2 to get the energy produced